Springfield is the third and current capital of the US state of Illinois and the county seat of Sangamon County with a population of 116,250 (U.S. Bureau of the Census, 2010), making it the sixth most populated city in the state and the second most populated Illinois city outside of the Chicago Metropolitan Area. It is the largest city in central Illinois. Just over 208,000 residents live in the Springfield Metropolitan Statistical Area, which includes Sangamon County and adjacent Menard County. Present-day Springfield was first settled by European Americans in the late 1810s, around the time Illinois became a state. The most famous past resident is Abraham Lincoln, who lived in Springfield from 1837 until 1861, when he went to the White House as President. Major tourist attractions include a multitude of historic sites connected with Lincoln.

The city lies on a mostly flat plain that encompasses much of the surrounding countryside. Hilly terrain lies near the Sangamon River. Lake Springfield, a large artificial lake owned by City Water, Light & Power company called CWLP, supplies the city with recreation and drinking water. Weather is fairly typical for middle latitude locations, with hot summers and cold winters. Spring and summer weather is like that of most midwestern cities; severe thunderstorms are common. Tornadoes hit Springfield in 1957 and 2006.

The city is governed by a mayor-council form of government. The city proper is also the "Capital Township" governmental entity. In addition, the government of the state of Illinois is also based in Springfield. State government entities located in the city include the Illinois General Assembly, the Illinois Supreme Court and the Office of the Governor of Illinois. There are three public and two private high schools in Springfield. Public schools in Springfield are operated by District No. 186. The economy of Springfield is marked by government jobs, which account for a large percentage of the city's workforce.